copy_entries
copy_entries(left, nr_left, right, 0, delta);
copy_entries(right, 0, left, target_left, delta);
copy_entries(left, nr_left, right, 0, left_short);
copy_entries(center, 0, right, left_short, target_center);
copy_entries(center, 0, left, target_left, left_to_center);
copy_entries(center, left_to_center, right, 0, target_center - left_to_center);
copy_entries(right, 0, left, nr_left - right_short, right_short);
copy_entries(center, 0, left, target_left, nr_left - target_left);